JP5556992B2 - Motor control device and vehicle seat control device - Google Patents

Description

  The present invention relates to a motor control device that controls a motor that displaces the position of a driven object.

  There is a mechanism in which different parts are driven by a plurality of motors to realize one collective movement as a whole. For example, some vehicle seats can be electrically switched using a motor between a seating state in which a user can sit and a storage state in which the space in the vehicle can be expanded. Japanese Unexamined Patent Publication No. 2007-62507 (Patent Document 1) discloses an example of such an electric seat device. The seat device is switched between a seated state and a retracted state by a user operating an operation switch. While the user continues to operate the operation switch, the seat cushion and the seat back are driven by the respective motors, and the seating state and the storage state are switched. At this time, on the midway route in which the sitting state and the retracted state are changed, the moving speed of at least one of the seat cushion and the seat back is changed from the initial moving speed of the one. This avoids mutual interference and reduces the total operating time by overlapping each other's travel time. In such a mechanism, it is important that each motor is controlled with high precision in cooperation.

JP 2007-62507 A (paragraphs 49-50)

  When there is a mechanical end point in the movable range of the movable part, such as a vehicle seat, when the motor reaches the end point with steady rotation, an impact sound is generated when the end point is mechanically stopped or uncomfortable. There is a possibility of causing vibration. For this reason, in the vicinity of the end point, it is preferable to perform a slow stop by performing a slow-down control that gradually reduces the rotational speed of the motor. Similarly, if the motor is operated at a steady rotational speed immediately after the operation, a sudden movement may occur or the motor may be overloaded. Therefore, it is preferable to perform a slow start by performing a slow-up control that gradually increases the rotation speed of the motor. However, even with slow start and slow stop, it is preferable that the series of operation time from the start of operation to the end of operation is as short as possible.

  Further, the posture of the vehicle seat is not a simple two state of a seating state and a retracted state. For example, the reclining angle of the seat back may be adjusted by the occupant even in the seating state. Therefore, the posture when the seat starts to move is not constant. When driving the motor with slow start and slow stop, regardless of the position and posture at the beginning of movement, if the control based on the target rotation speed specified by the seat position is executed, the movement of the seat is not uniform and the user feels uncomfortable. Cheap. Therefore, it is preferable that the series of operations from the operation start to the operation end is a unified operation regardless of the operation start position.

  Also, at the time of slow start, the motor rotation speed is low particularly at the initial stage. For example, in a system that calculates an actual rotational speed based on a pulse signal from a hall sensor, the resolution of the actual rotational speed becomes rough, and the update of the actual rotational speed may be delayed. As a result, there is a possibility that feedback control based on the deviation between the target rotational speed and the detected actual rotational speed does not function effectively. On the other hand, if simple feed-forward control is performed here, the difference between the actual motor speed and the target speed increases because the sliding resistance varies depending on the mechanical aging of the motor and seat and the environmental temperature. There is a case. As a result, the motor may stop due to insufficient torque. Therefore, it is preferable that the motor is controlled by a control method having a strong resistance to an operating environment such as aged deterioration, environmental temperature, and power supply voltage fluctuation.

  As described above, particularly when a plurality of motors operate in cooperation to drive one mechanism, each motor needs to be controlled with high accuracy. Therefore, motor control in which various problems as described above are suppressed is required. Of course, the above-mentioned problem is shared even when a single motor drives one mechanism without cooperation of a plurality of motors.

  In view of the above problems, a series of operations from the start of operation to the end of operation can be completed in the shortest possible time, and there is a sense of unity in the series of operations without depending on the operation start position. A motor control technology having strong resistance to an operating environment such as environmental temperature and power supply voltage fluctuation is desired.

The characteristic configuration of the motor control device according to the present invention is as follows:
The target rotational speed is set for each predetermined calculation period until the target rotational speed of the motor reaches the upper limit rotational speed set according to the position reached from the reference position of the driven object whose position is displaced by being driven by the motor. An accelerating part to increase,
After the target rotational speed reaches the upper limit rotational speed, a speed reduction unit that decreases the target rotational speed of the motor for each calculation cycle;
A main control unit that drives and controls the motor based on the target rotational speed;
A limiting unit that limits the rotation of the motor according to an allowable output allowed by the motor, and
The upper limit rotational speed is a value that decreases as the amount of displacement from the reference position increases with the final steady rotational speed at which the motor is driven at a constant speed as a minimum value, To reduce the target rotational speed according to
Point the limiting unit, when the output of the motor reaches the allowable output limits the increase of the target speed by the acceleration unit, to set the target rotational speed on the current rotational speed of the motor It is in.

  According to this feature configuration, the target rotational speed is increased until the target rotational speed of the motor reaches the upper limit rotational speed, so that the time required for accelerating the motor and completing a series of operations of the driven object can be shortened. Goals are set well. In addition, since the target rotational speed is decreased after the target rotational speed reaches the upper limit rotational speed, the target rotational speed that can reduce the motor and suppress the impact when the drive target is stopped is set well. Is done. The main control unit drives and controls the motor based on such a target rotational speed. Therefore, the driven object can complete a series of operations from the start of the operation to the end of the operation in as short a time as possible, and the occurrence of mechanical discomfort such as impact is also suppressed. In addition, since the upper limit number of rotations is set according to the position of the drive object from the reference position, a series of operations from the start of operation to the end of operation is not dependent on the drive start position of the drive object. Is executed with a sense of unity. In addition, since the upper limit number of rotations is set according to the position of the driven object from the reference position, the maximum speed that the motor can output at that time is affected by the operating environment such as aging, environmental temperature, power supply voltage fluctuation, etc. Even if it decreases, the influence on the position where acceleration and deceleration are performed is small. In other words, even if the operation time is extended, the series of operations from the start to the end of the operation is extended to a similar shape with a sense of unity, so that the user is unlikely to feel uncomfortable. Therefore, a motor control device having high resistance to the operating environment is realized.

Further, if the upper limit rotational speed is a value that decreases as the amount of displacement from the reference position increases, the upper limit rotational speed is sufficiently low even when the position where the rotational speed reaches the upper limit rotational speed is the final stage of the displacement. Number of revolutions. Accordingly, it is easy to reduce the target rotational speed up to the final steady rotational speed. As a result, the target rotational speed can be smoothly changed from increasing to decreasing. In addition, since the reduction unit reduces the target rotation number according to the upper limit rotation number, the change rate of the upper limit rotation number matches the deceleration rate by the reduction unit, so that it is not affected by the arrival position of the driving object, The target rotational speed can be smoothly changed from increasing to decreasing from any position.

Further, when the power supply voltage is low or the load on the motor becomes heavy, the output of the motor may not be able to follow the increasing target rotational speed. Since the target rotation speed is set to the actual rotation speed of the motor, it is determined that the target rotation speed (in this case, the actual rotation speed) has exceeded the upper limit rotation speed, and the motor is within the allowable range until deceleration control is started. It will function to the fullest within. As a result, the driving of the driven object can be completed in as short a time as possible even under the condition where the restriction is applied.

  Furthermore, it is preferable that the upper limit rotational speed decreases with a decreasing rate that increases continuously or stepwise as the amount of displacement from the reference position increases. In this way, the upper limit rotational speed decreases rapidly as the amount of displacement from the reference position increases. Therefore, when the driven object completes the displacement, a strong feeling of deceleration can be generated.

  Here, when the main control unit controls the motor by pulse width modulation, the limiting unit sets the output of the motor to the allowable value when the duty of the pulse width modulation is equal to or greater than a predetermined upper limit duty. It is preferable to limit by determining that the output has been reached and setting the duty of pulse width modulation to the upper limit duty. Since the duty of the pulse width modulation is substantially fixed to the upper limit duty, the driving of the driven object can be completed in as short a time as possible even under the condition that the restriction is applied.

  In the motor control device according to the present invention, the main control unit controls the motor by pulse width modulation, and feeds until the driving object is displaced by a predetermined initial movement amount from the start of driving. When the forward control is executed and the feedback control is executed after the displacement exceeding the initial movement amount, when the motor rotation speed is lower than the target rotation speed in the feedforward control, the pulse is It is preferable to increase the width modulation duty by a predetermined amount for each calculation cycle.

  In feed-forward control, basically, the actual rotational speed (rotational speed) of the motor is not referred to, so the actual rotational speed of the motor may deviate greatly from the target rotational speed. However, when the rotational speed of the motor is lower than the target rotational speed, this difference can be eliminated or suppressed by adding a correction process for increasing the duty of pulse width modulation by a predetermined amount for each calculation cycle. .

  When adding such correction processing, the main control unit preferably increases the duty of pulse width modulation when the difference between the target rotational speed and the rotational speed of the motor is greater than or equal to a predetermined tolerance. is there. By providing the tolerance, it is possible to suppress erroneous correction processing from being executed even if the measurement accuracy (resolution or the like) of the rotation speed of the motor is low. In addition, resistance due to noise or the like is increased, and it is possible to suppress erroneous correction processing from being executed.

  Further, when the motor control device according to the present invention includes a stop determination unit that determines that the motor has been stopped based on the rotational speed of the motor, the correction process is executed in the following manner. It is preferable. That is, when the predetermined amount by which the duty of the pulse width modulation is increased is determined by the main control unit to be lower than the target rotation number by a predetermined value, the stop determination unit is It is preferable that the increase amount reaches 100% from the duty at the time of starting the motor before the stop state is determined.

  When the motor speed is lower than the target speed, other objects may be in contact with the object to be driven, or the displacement may be hindered, or the load may be affected by aging or the operating environment. May increase. When the load is increased due to aging or the influence of the operating environment, it is preferable to correct as soon as possible to increase the output of the motor. For example, when the displacement of the driven object is obstructed due to the influence of dust or dirt, the obstruction may be eliminated by increasing the output. Before the stop determination unit determines the stop state of the motor, by increasing the duty by an increase amount that can make the duty 100%, the motor output is determined before the stop of the motor is determined. Can be increased as much as possible.

  In the motor control device according to the present invention, the main control unit controls the motor by pulse width modulation, and feeds until the driving object is displaced by a predetermined initial movement amount from the start of driving. When performing forward control and performing feedback control after displacement exceeding the initial movement amount, when shifting from feedforward control to feedback control, the rotational speed of the motor at the time of the transition is set. It is preferable to update the target rotational speed to a value obtained by adding a predetermined offset value.

  If the difference between the actual rotation speed and the target rotation speed is large at the time of transition from feedforward control to feedback control, the difference is rapidly corrected by the feedback control that is started. To do. For example, when the motor is driven with a low load, the actual rotational speed becomes larger than the target rotational speed, and the rotational speed may rapidly decrease after shifting to feedback control. When the motor is driven with a high load, the actual rotational speed is smaller than the target rotational speed, and the rotational speed may rapidly increase after shifting to feedback control. Such fluctuation naturally leads to disturbance of the movement of the driven object. Therefore, at the start of the feedback control, the fluctuation of the rotational speed at the time of control switching can be suppressed by updating the target rotational speed to a value obtained by adding a predetermined offset value to the rotational speed of the motor. As a result, the transition from feedforward control to feedback control is smooth. In the feedback control, since there is a control delay between the target rotational speed and the actual rotational speed following the target rotational speed, it is preferable that the offset value is set based on the amount of the control delay.

  Further, it is preferable that the acceleration unit of the motor control device according to the present invention increases the target rotational speed at different increase rates when the main control unit executes feedforward control and when feedback control is executed. It is.

  For example, since the feedforward control is control at the start of driving of the motor, it is preferable to slow start the motor. On the other hand, in the feedback control, since the motor is already in a rotating state, the motor may be rotated at a higher speed. Therefore, when the target rotation speed is increased at different rates when the feedforward control is executed and when the feedback control is executed, a series of operations from the operation start to the operation end can be completed in a short time. .

  Further, it is preferable that the acceleration unit of the motor control device according to the present invention increases the target rotational speed with an increasing rate that increases continuously or stepwise as the amount of displacement from the reference position increases. .

  Although it is preferable to start the motor slowly, if it is already in a rotating state, it can be rotated at a higher speed. By increasing the target rotational speed with an increasing rate that increases as the amount of displacement from the reference position increases, a series of operations from the operation start to the operation end can be completed in a short time.

  A vehicle seat control device according to the present invention includes any one of the motor control devices described above, and drives a vehicle seat as the drive object. The vehicle seat is highly likely to be adjusted to various angles by the occupant, and the position (displacement start position) at the time of starting the displacement is highly likely to fluctuate. However, it is preferable to have a sense of unity in a series of movements of displacement, and it is preferable to execute control by the motor control device. Further, when the posture or position of the vehicle seat is displaced, it is sufficient to displace it to a mechanical end point. However, it is preferable that the vehicle seat is sufficiently decelerated and stopped without causing an impact. Also in this respect, the control by the motor control device is preferable.

Block diagram schematically showing an example of the configuration of a motor control device The figure which shows the control outline with the relationship between the position of the driven object and the target rotational speed of the motor The figure which shows the concept of the duty restriction | limiting by a restriction | limiting part Diagram showing the relationship between power supply voltage and duty limit The figure which shows an example of the control outline in the case of performing acceleration and deceleration at a multi-step speed The figure which shows the conditions which perform low-speed rotation determination based on the waveform of a rotation sensor The figure which shows the example which correct | amends a duty at the time of low-speed rotation determination The figure which shows the example which the rotation speed of the motor is disturbed at the time of control change Diagram showing an example of correcting the target speed when the control is switched (at low load) The figure which shows the example (at the time of high load) which corrects the target number of rotations when control changes Diagram showing the effect of switching control Overall flow chart of motor speed control Flowchart of feedforward control that is one of the sub-processes Flow chart of feedback control that is one of the sub-processes Flow chart of restriction control that is one of the sub-processes 12 is a flowchart showing another embodiment of FIG. The figure which shows an example of the attitude | position change of a vehicle seat The figure which shows the other example of the attitude | position change of a vehicle seat A perspective view showing an example of a vehicle

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The motor control device according to the present invention controls the motor in accordance with the position of the driven object that is driven by the motor and whose position is displaced. Examples of the driving object include an automatic door of a building, an electric seat of a vehicle, a sliding door, and a power window. As shown in FIG. 1, in the present embodiment, the motor control device is configured as an ECU (electronic control unit) 10 having a central processing unit (CPU) 11 as a core. The ECU 10 includes a program memory 12 and a driver circuit 13. The program memory 12 stores a program as software executed by the CPU 11. The driver circuit 13 is a circuit for driving the motor 30 by converting the output of the CPU 11, which is generally a low voltage circuit, into a motor drive voltage higher than the power supply voltage of the CPU 11. The motor control device has various functional units denoted by reference numerals 1 to 5 in FIG. 1, and these functional units are stored in hardware represented by the CPU 11 and the driver circuit 13 and the program memory 12. Realized by collaboration with other software. Such a configuration is merely an example, and does not prevent the ECU 10 from being configured by a DSP (digital signal processor), other logic processors, logic circuits, or the like.

  The motor 30 is provided with a rotation sensor 31 that detects its rotation. The rotation sensor 31 may be built in the motor 30. The rotation sensor 31 includes, for example, a Hall IC. In the present embodiment, the rotation sensor 31 is a low-resolution and inexpensive sensor that outputs a one-period pulse signal MP when the motor 30 rotates once. Of course, the rotation sensor 31 having a higher resolution than this may be used, but in the present embodiment, as will be described later, good control can be realized even with such a rotation sensor 31 having a lower resolution. . The ECU 10 can know the position of the driving object whose position is displaced by being driven by the motor 30 from the number of pulses of the pulse signal MP. Therefore, the rotation sensor 31 not only detects the rotation speed and rotation speed of the motor 30, but also functions as a position sensor that detects the position of the drive object.

  When the motor 30 is driven by being supplied with electric power from a battery, for example, when the motor 30 is a motor mounted on a vehicle, the voltage of the supplied electric power may vary. Therefore, the detection result of the voltmeter (voltage sensor) 41 that measures the power supply voltage of the battery 40 is input to the ECU 10. The ECU 10 drives and controls the motor 30 in consideration of the power supply voltage supplied to the motor 30.

  As shown in FIG. 1, the ECU 10 (motor control device) has a plurality of functional units including a main control unit 1, an acceleration unit 2, a limiting unit 3, a deceleration unit 4, and a stop determination unit 5. The function of each functional unit will be described with reference to FIG. 2 showing an outline of control of the motor 30 by the motor control device in relation to the position of the driving object and the target rotational speed VT of the motor. The main control unit 1 is a functional unit that drives and controls the motor 30 based on the target rotational speed VT. In the present embodiment, the main control unit 1 controls the motor 30 by pulse width modulation (PWM). The acceleration unit 2 starts the target rotation speed (when the motor 30 starts up) until the target rotation speed VT of the motor 30 reaches the upper limit rotation speed VL set in accordance with the position where the drive target object reaches from the reference position (zero). This is a functional unit that increases the initial rotational speed (VS) at every predetermined calculation cycle. After the target rotational speed VT reaches the upper limit rotational speed VL, the deceleration unit 4 decreases the target rotational speed VT of the motor 30 every calculation cycle until the motor 30 reaches the final steady rotational speed VE that is driven at a constant speed. It is a functional part. In the present embodiment, the calculation cycle indicates the calculation cycle of the CPU 11, and is, for example, a time for executing a series of processes in FIG. At the start of the calculation cycle, a series of processing in FIG. 12 is executed when a driving instruction for the driving object is given from the host controller 50.

  FIG. 2A illustrates a case where the drive object starts displacement from a zero position, which is the reference position, and FIG. 2B illustrates that the drive object starts displacement from a position other than the reference position. The case is shown as an example. As is clear from FIGS. 2A and 2B, the transition of the target rotational speed VT of the motor 30 is similar regardless of the displacement start position (SP) of the driven object. Therefore, the driven object apparently moves from the start of displacement to the end of displacement regardless of the displacement start position SP. Therefore, the movement of the driving object makes the user feel a sense of unity.

  In this way, in order to create a sense of unity and to make the transition of the target rotational speed VT similar, the upper limit rotational speed VL decreases as the displacement from the reference position increases with the lowest value as the final steady rotational speed VE. It is preferable that the value be The target rotational speed VT is decelerated to the final steady rotational speed VE by the speed reduction unit 4 after reaching the upper limit rotational speed VL. That is, the deceleration unit 4 decreases the target rotational speed VT as the amount of displacement from the reference position increases.

  Here, with reference to FIG. 2, the relationship between the target rotational speed VT of the motor 30 and the displacement of the position of the driven object is organized. At the displacement start position SP, the initial rotational speed VS is set as the target rotational speed VT. The initial rotational speed VS is set to a rotational speed at which the motor 30 can smoothly start rotating. Next, the target rotational speed VT is gradually increased by the control of the acceleration unit 2 as a main body. That is, the slow start is performed in which the motor 30 is gradually slowed up from the low-speed initial rotational speed VS. As will be described later, when the motor 30 starts to rotate, the main control unit 1 drives and controls the motor 30 by feedforward control (FF control). Then, the main control unit 1 switches to drive control by feedback control (FB control) after the drive target is displaced by a certain initial movement amount MV in the course of slow-up.

  When the motor 30 is slowed up and the target rotational speed VT reaches the upper limit rotational speed VL, the target rotational speed VT is gradually decreased under the control of the speed reduction unit 4. That is, the motor 30 is gradually slowed down from the high-speed upper limit rotational speed VL. When the target rotational speed VT decreases to the final steady rotational speed VE, the target rotational speed VT is held at the final steady rotational speed VE. In other words, the steady operation is performed after this, but it can also be regarded as a deceleration process with a reduction rate of zero, and may be considered as the control of the deceleration unit 4 including this steady operation. The final steady rotational speed VE is sufficiently low, and this speed is maintained, and the driven object continues to be displaced to the mechanical end point (displacement completion position EP). For example, if an elastic body such as rubber is disposed at the end point, the driven object that has reached the end point at a sufficiently low speed completes the displacement without causing an impact. Therefore, the slow stop is performed by the slow down and the steady operation by the control of the deceleration unit 4 main body. Since the control of the deceleration unit 4 main body is performed following the control of the acceleration unit 2 main body, it is after switching from the feedforward control to the feedback control, and the motor 30 is controlled by feedback control throughout the control of the deceleration unit 4 main body. Is driven and controlled.

  The limiting unit 3 is a functional unit that limits the number of rotations of the motor 30 according to the allowable output allowed by the motor 30. Specifically, as illustrated in FIG. 3, the limiter 3 limits the increase in the target rotational speed VT by the acceleration unit 2 when the output of the motor 30 reaches an allowable output. Then, limiting unit 3 sets target rotational speed VT to an actual rotational speed (VP) that is the actual rotational speed of motor 30 until target rotational speed VT reaches upper limit rotational speed VL. Even if the increase in the target rotational speed VT is limited by the limiting unit 3, the motor 30 continues to rotate, so that the driven object continues to be displaced. As described above, the upper limit rotational speed VL is preferably a value that decreases as the displacement of the driven object increases. Therefore, even if the target rotational speed VT is fixed at the actual rotational speed (VP), the maximum rotational speed VL is reached when the amount of displacement increases. In practice, the value of the upper limit rotational speed VL that decreases will reach the target rotational speed VT fixed by the limitation.

  Here, it is preferable that the allowable output allowed for the motor 30 is defined by the duty D of the pulse width modulation. As shown in FIG. 3, in the present embodiment, the limiting unit 3 indicates that the output of the motor 30 has reached the allowable output because the duty D of the pulse width modulation by the main control unit 1 has reached a predetermined upper limit duty DL. Determine. The upper limit duty DL is 90%, for example. The duty at the start of control of the motor 30 (starting duty DS) is calculated by the power supply voltage (BV) of the motor 30, for example, the voltage of the battery 40. An example of the duty limit shown in FIG. 3 is a case of a standard voltage (for example, 12V). FIG. 4 shows a restriction example of a case where the voltage is higher than the standard voltage (for example, 14V) and a case where the voltage is lower (for example, 10V) together with the standard voltage. A broken line DN in FIG. 4 indicates the duty D when the power supply voltage (BV) is a standard voltage, and a section in which the restriction is applied is indicated by a broken line arrow.

  A solid line DH in FIG. 4 indicates the duty D when the power supply voltage (BV) is a high voltage. If the power supply voltage (BV) is a high voltage, the motor 30 can be driven even if the duty D (DH) is small, so the starting duty DS (DSH) is a small value. Since the starting duty DSH is a small value, there is a margin up to the upper limit duty DL. In the example shown in FIG. 4, even if the rotational speed is increased to the upper limit rotational speed VL, the duty D (DH) does not reach the upper limit duty DL and the restriction by the restriction unit 3 is not performed.

  A solid line DL in FIG. 4 indicates the duty D when the power supply voltage (BV) is a low voltage. If the power supply voltage (BV) is low, the motor 30 cannot be driven unless the duty D (DL) is increased, and the starting duty DS (DSL) is a large value. Since the starting duty DSL is a large value, there is little margin to the upper limit duty DL. In the example shown in FIG. 4, the duty D reaches the upper limit duty DL before the rotation speed is increased to the upper limit rotation speed VL. Naturally, the duty D (DL) reaches the upper limit duty DL at a position where the displacement of the driven object is smaller than in the case of the standard voltage.

  In the example shown in FIGS. 2 to 4, the acceleration by the acceleration unit 2 and the deceleration by the deceleration unit 4 are constant. However, the present invention is not limited to this, and the accelerating unit 2 may increase the target rotational speed VT with an increasing rate that increases as the amount of displacement from the reference position increases. Since the target rotational speed VT rises quickly, it is possible to shorten the time for which the driven object is displaced. Further, as described above, the control mode is switched from the feedforward control to the feedback control in the course of the control of the acceleration unit 2 main body. As shown in FIG. 5, the acceleration unit 2 may increase the target rotational speed VT at different increasing rates when the main control unit 1 executes the feedforward control and when the feedback control is executed. Similarly, as shown in FIG. 5, the upper limit rotational speed VL may decrease with a decreasing rate that increases as the amount of displacement from the reference position increases. When the target rotational speed VT decreases rapidly as the final steady rotational speed VE approaches, the displacement of the driven object decreases rapidly, and a feeling of deceleration can be generated.

  As described above, when the motor 30 starts to rotate, the main control unit 1 drives and controls the motor 30 by feedforward control. In the feedforward control, the target rotational speed VT is increased at a predetermined increase rate, so the actual rotational speed (VP) of the motor 30 is not directly reflected. Therefore, there is a possibility that the target rotational speed VT and the actual rotational speed VP may deviate due to mechanical wear of the driven object and environmental conditions such as temperature and humidity. The difference between the target rotation speed VT and the actual rotation speed VP can be determined by the elapsed time from the pulse update of the pulse signal MP of the rotation sensor 31. The pulse update is a time when the logic of the pulse signal MP is inverted, and the elapsed time from the pulse update is a time Ts (Ts1 to Ts4) after the logic is inverted as shown in FIG.

  The ECU 10 (main control unit 1) checks the elapsed time Ts every calculation cycle. When the elapsed time Ts exceeds the value obtained by adding the allowable value Δs to the predetermined pulse interval Tt, the main control unit 1 determines that the target rotational speed VT and the actual rotational speed VP have deviated. The predetermined pulse interval Tt is a pulse interval when the motor 30 rotates at the target rotation speed VT. Accordingly, when the sum of the predetermined pulse interval Tt4 (Tt) and the allowable value Δs is exceeded as in the elapsed time Ts4 shown in FIG. 6, the main control unit 1 determines the cycle based on the target rotational speed VT and the actual rotational speed. It is determined that the difference from the cycle based on VP is large. That is, the main control unit 1 determines that the two have deviated when the difference between the target rotational speed VT and the actual rotational speed VP is equal to or greater than a predetermined tolerance. Based on the determination result, the main control unit 1 executes a correction process for increasing the duty D of the pulse width modulation. Thereby, as shown in FIG. 7, the actual rotational speed VP approaches the target rotational speed VT. In the present embodiment, the main control unit 1 increases the duty D of the pulse width modulation by a predetermined amount (Δd) for each calculation cycle within the correction period TC. The correction period TC is a period shorter than the period CP shown in FIG. 7, and the predetermined amount Δd by which the duty D is increased is an increase amount by which the duty D reaches 100% within the correction period TC.

  A period CP shown in FIG. 7 is set in relation to the stop determination unit 5. The stop determination unit 5 is a functional unit that determines that the motor 30 is stopped based on the actual rotation speed VP that is the actual rotation speed of the motor 30. As described above, the elapsed time Ts from the pulse update becomes longer as the actual rotational speed VP of the motor 30 becomes lower. For example, when the displacement of the driving object is obstructed, the rotation of the motor 30 mechanically connected to the driving object is also obstructed, so that the actual rotational speed VP is lowered. When the object to be driven cannot be displaced, the rotation of the motor 30 is also stopped, the pulse signal MP is not updated, and the elapsed time Ts from the pulse update continues. When this elapsed time exceeds a predetermined threshold value, the stop determination unit 5 determines that the motor 30 has been stopped. A period CP shown in FIG. 7 corresponds to this predetermined threshold value.

  The predetermined amount Δd by which the pulse width modulation duty D is increased is determined by the stop determination unit 5 from the time when the main control unit 1 determines that the actual rotation speed VP is lower than the predetermined value with respect to the target rotation speed VT. It is preferable that the duty D is an increase amount that reaches 100% until the stop state is determined. Considering increasing the duty D immediately after the start of displacement, the predetermined amount Δd is preferably an increase amount that can reach 100% from the starting duty DSH at the time of high voltage during the period CP. For example, if the driving object is a vehicle seat, the displacement of the driving object is assumed to be a scene where the grease of the movable part is cured and the sliding resistance is increased in a low temperature environment.

  Further, as described above, the main control unit 1 executes the feedforward control until the driven object is displaced by the predetermined initial movement amount MV from the driving start (displacement start position SP), and exceeds the initial movement amount MV. After the displacement, feedback control is executed. Here, the main control unit 1 increases the duty D as described above when the difference between the target rotational speed VT and the actual rotational speed VP is more than a predetermined tolerance during the execution of the feedforward control. Make corrections. However, this is not feedback that makes the actual rotational speed VP coincide with the target rotational speed VT, but the duty D is increased by a predetermined amount Δd for each calculation cycle. Accordingly, there may be a case where the difference between the target rotational speed VT and the actual rotational speed VP is still large at the time of shifting from the feedforward control to the feedback control. Further, when the actual rotational speed VP is higher than the target rotational speed VT, the displacement of the drive target is in a direction that becomes faster. Therefore, there is little need to reduce the difference until the duty is reduced by the correction process. Therefore, there is a possibility that the actual rotational speed VP greatly exceeds the target rotational speed VT at the time of transition from feedforward control to feedback control.

  If the difference between the actual rotational speed VP and the target rotational speed VT is large at the time of transition from the feedforward control to the feedback control, the difference is rapidly corrected by the feedback control that is started. A large fluctuation occurs in the actual rotational speed VP. For example, when the motor 30 is driven with a low load, the actual rotational speed VP becomes larger than the target rotational speed VT, and fluctuations such that the actual rotational speed VP rapidly decreases after shifting to feedback control. Arise. When the motor 30 is driven with a high load, the actual rotational speed VP becomes smaller than the target rotational speed VT, and fluctuations occur such that the actual rotational speed VP increases rapidly after shifting to feedback control. Such fluctuation naturally leads to disturbance of the movement of the driven object. As shown in FIG. 8, in the feedback control, there is a predetermined control delay CR between the target rotational speed VT and the actual rotational speed VP following the target rotational speed VT. In this example, a control delay CR that is lower than the target rotational speed VT is illustrated. Further, the size of the control delay CR is exaggerated for easy understanding.

  Therefore, as shown in FIGS. 9 and 10, when the main control unit 1 shifts from the feedforward control to the feedback control, the main control unit 1 sets a predetermined rotational speed VP that is the actual rotation speed of the motor 30 at the time of the shift. The target rotational speed VT is updated to a value obtained by adding the offset value α. It will be easily understood that the offset value α is preferably set based on the control delay CR described above. FIG. 9 illustrates the case where the motor 30 rotates at a low load, and FIG. 10 illustrates the case where the motor 30 rotates at a high load. By adjusting the target rotational speed VT in this way, the transition from the feedforward control to the feedback control becomes smooth.

  In the present embodiment, the main control unit 1 performs feedforward control from the start of driving until it is displaced by a predetermined initial movement amount MV, and performs feedback control after displacement exceeding the initial movement amount MV. FIG. 11A shows an example of the actual rotational speed VP of the motor 30 when the feedback control is executed immediately after the start of driving. FIG. 11B is an example of the actual rotational speed VP in the present embodiment in which feedforward control and feedback control are performed on the same target rotational speed VT as in FIG. If feedback control is executed immediately after the start of driving, large hunting occurs in the actual rotational speed VP as shown in FIG. In particular, when the low-resolution rotation sensor 31 is used as in this embodiment, the tendency becomes remarkable and it takes time to converge. On the other hand, when the feedforward control is executed at the start of driving, the actual rotational speed VP follows the target rotational speed VP well as shown in FIG. 11B without being affected by the detection result of the low-resolution rotational sensor 31. To do.

  Hereinafter, motor control procedures for realizing various functions as described above will be described with reference to the flowcharts of FIGS. The speed control by the ECU 10 is performed, for example, by repeatedly executing a series of processes shown in FIG. Here, as an example, this calculation cycle is 5 ms. At the beginning of one calculation cycle, it is determined whether or not this iterative process is the first calculation (# 1). The ECU 10 executes a speed control program for the motor 30 in response to a command from the controller 50 that is higher than the ECU 10. Process # 1 is a determination as to whether or not it is immediately after the execution is started by a command from the host controller 50. As shown below, when it is determined that the calculation is an initial calculation, an initial value setting process is executed (# 2). Therefore, process # 1 is equivalent to determining whether or not the initial value setting has been completed.

  As an example, in the initial value setting process # 2, the deceleration start flag F is set to an OFF state, and the target rotational speed VT is set to an initial value (for example, 1000 rpm). Further, since the position is stored in a storage unit such as a register or a memory of the CPU 11 when the driven object is stopped in the previous speed control, the position information is read from the storage unit. The read position information is a position at the start of operation, that is, a displacement start position SP. The target rotational speed VT is stored in the program memory 12, other registers, memory, and the like. When the initial value setting is completed (when the initial value setting has been completed), values of the current rotational speed (actual rotational speed) VP of the motor 30, the current position PP of the driven object, and the power supply voltage BV are acquired. (# 3). At the time of the first calculation, the current position PP is equal to the displacement start position SP.

  Next, it is determined whether or not the current position PP is a position that exceeds the initial movement amount MV (# 4). Specifically, if the current position PP exceeds the value obtained by adding the initial movement amount MV to the displacement start position SP, the driven object has displaced the initial movement amount MV, and as shown in FIG. In addition, the determination is performed using the initial movement amount MV, the displacement start position SP, and the current position PP. When the driven object is not displaced beyond the initial movement amount MV, the target rotational speed VT is increased by the first increase amount A1 (# 8), and feedforward control (FF control) is executed ( # 10). The increase amount A1 is, for example, +4 rmp / 5 ms (5 ms: calculation cycle).

  The feedforward control (# 10) is executed according to the procedure shown in FIG. First, the duty D of PWM control is calculated (# 11). In the present embodiment, the duty D is obtained by multiplying the target rotational speed VT by a proportional gain (FFgain) of feedforward control. The duty D is calculated as a value at a standard power supply voltage (for example, 12V). Next, the duty D is corrected based on the power supply voltage BV acquired in the process # 3 (# 12). Next, as described above with reference to FIGS. 6 and 7, the elapsed time Ts from the previous pulse update is calculated (# 13), and the pulse interval Tt when the motor 30 is driven at the current target rotational speed VT. Is calculated (# 14). Subsequently, it is determined whether or not the elapsed time Ts from the pulse update is equal to or greater than a value obtained by adding a predetermined allowable value Δs to a predetermined pulse interval Tt (# 15). As a result, the duty D is increased by a predetermined amount Δd (# 16).

  For example, it is assumed that the elapsed time Ts corresponding to the time CP (see FIG. 7) serving as a reference for the stop determination unit 5 to determine that the motor 30 has been stopped is 300 ms. When the calculation cycle is 5 ms, 60 repetitive calculations are executed during 300 ms. The predetermined amount Δd is set to a value that allows the duty D to reach 100% from the start duty DHS (see FIG. 4) when the voltage is high during the 60 times. For example, when the starting duty DHS is 10%, Δd is 1.5% (= 90% / 60 times). Actually, the maximum value of the duty D is set as the upper limit value DF. The upper limit value DF can be set to, for example, a value of about 85 to 95%, but is preferably a value equal to or lower than the upper limit duty DL when the duty is limited by the limiting unit 3, for example, set to about 85%. Is preferred. When the duty D increased in the process # 16 becomes equal to or higher than the upper limit value (# 17), the duty D is set to the upper limit value DF (# 18). However, in order to prepare for the feedback control executed following the feedforward control, the duty D calculated in the process # 16 is updated as an internal value for feedback control (# 19).

  The process # 8 for increasing the target rotational speed VT by the first increase amount A1 and the feedforward control # 10 executed subsequent to the process # 8 are processes executed mainly by the acceleration unit 2. In particular, the process 8 is a representative and central process executed by the acceleration unit 2. The main control unit 1 executes feedforward control # 10 in cooperation with the acceleration unit 2, and drives and controls the motor 30 using a predetermined duty D.

  In the process # 4, when the driven object has completed the displacement of the initial movement amount MV, the upper limit rotational speed VL of the target rotational speed VT is calculated according to the current position PP (# 5). This calculation may be arithmetically performed based on a mathematical expression or the like, or may be a reference calculation from a map or table stored in the program memory 12 or other storage unit. Next, in the process # 6, it is determined whether the control of the acceleration unit 2 main body is executed (No branch) or whether the deceleration flag F is turned on and the control of the speed reduction unit 4 main body is executed (Yes branch). . The feedforward control described above is also the control mainly by the acceleration unit 2, and it can be said that the process # 6 is a determination of whether to continue the control in the acceleration phase or to shift to the deceleration phase.

  In process # 6, if it is confirmed that the target rotational speed VT has not reached the upper limit rotational speed VL and that the deceleration start flag F is not ON, then the determination of process # 7 is executed. In process # 7, it is determined whether or not the current duty D (duty D determined in the previous repetitive process) has reached the upper limit duty DL. The upper limit duty DL is 90%, for example. When the duty D reaches the upper limit duty DL (Yes branch), the limit control # 40 is executed through the process # 9b. When the duty D does not reach the upper limit duty DL (No branch), feedback control (FB control) # 20 is executed through the process # 9a. In the determination in the process # 6, instead of “the target rotational speed VT has not reached the upper limit rotational speed VL”, “the actual rotational speed VP has not reached the upper limit rotational speed VL” may be used. Is possible.

  First, feedback control # 20 will be described. If it is determined in process # 7 that the duty D is less than the upper limit duty DL, the target rotational speed VT is increased by the second increase amount A2 in process # 9a, and feedback control (FB control) is executed (#). 20). The increase amount A2 is preferably a value larger than the first increase amount A1 during the feedforward control, for example, +10 rpm / 5 ms. Further, as described above with reference to FIG. 5, it may be configured to further accelerate to a third increase amount A3 (+15 rpm / 5 ms) (not shown) or the like according to the arrival position. When shifting to the feedback control, since the motor 30 is already rotating, it is possible to rotate the motor more stably than at the start of rotation.

  The feedback control # 20 is executed according to the procedure shown in FIG. First, it is determined whether or not it is the first calculation of feedback control, that is, whether or not it is the calculation cycle at the time of transition from feedforward control to feedback control (# 21). If it is determined that it is the first calculation of feedback control, the target rotational speed VT is updated to a value obtained by adding the offset value α to the current rotational speed VP (# 22). This is a process for smoothly performing the transition from the feedforward control to the feedback control as described with reference to FIGS. When the target rotational speed VT is set, an integral proportional control (IP control) calculation known in control engineering is executed (# 23), and the motor 30 is driven based on the determined duty D.

  The process # 9a for increasing the target rotational speed VT by the second increase amount A2 and the feedback control # 20 executed following the process # 9a are also processes executed mainly by the acceleration unit 2. In particular, the process 9a is a representative and central process executed by the acceleration unit 2. The main control unit 1 executes feedback control # 20 in cooperation with the acceleration unit 2, and drives and controls the motor 30 using a predetermined duty D.

  On the other hand, if it is determined in process # 7 of FIG. 12 that the duty D is equal to or greater than the upper limit duty DL, the target rotational speed VT is fixed to the current rotational speed VP in process # 9b, and limit control is executed (#). 40). As described above with reference to FIGS. 3 and 4, the limit control # 40 is executed until the current rotational speed VP reaches the upper limit rotational speed DL that decreases as the amount of displacement from the reference position increases. Specifically, as shown in FIG. 15, the duty D is set to the upper limit duty DL (# 41). However, in order to prepare for feedback control during deceleration after the current rotational speed VP reaches the upper limit rotational speed DL, the duty D is updated as an internal value for feedback control (# 42). This can also be called a limiting phase during the acceleration phase.

  The processes after process # 7 in FIG. 12 are processes executed mainly by the acceleration unit 2. However, the process # 9b and the process # 40 following the process # 9b are processes that are executed mainly by the limiting unit 3 that cooperates with the acceleration unit 2. In particular, the process 9b and the process # 41 are representative and central processes executed by the restriction unit 3. The main control unit 1 drives and controls the motor 30 using a predetermined duty D in cooperation with the acceleration unit 2 and the limiting unit 3. The restriction control # 40 is executed only when the duty D reaches the upper limit duty DL in the acceleration phase. Therefore, since the constant speed phase does not necessarily exist in the acceleration phase, the motor 30 is sufficiently accelerated when it can rotate quickly, and the operation of the driven object can be completed early.

  In the process # 6 of FIG. 12, when the deceleration flag F is in the ON state, or when the target rotation speed VT is equal to or higher than the upper limit rotation speed VL, the control mainly performed by the deceleration section 4 is executed. . That is, the acceleration phase shifts to the deceleration phase. First, the deceleration flag F is set to the ON state (# 31). If the deceleration flag F is already ON, it is reset. Next, it is determined whether or not the deceleration of the target rotational speed VT should be continued (# 32). By the deceleration control, the target rotational speed VT is decreased by a predetermined decrease amount B every calculation cycle, and therefore it is determined whether or not it is equal to or greater than the deceleration end value when the decrease amount B is subtracted from the target rotational speed VT. (# 32). The deceleration end value is preferably the final steady rotational speed VE (see FIGS. 2 and 5). The final steady rotational speed VE can be set to, for example, 1200 rpm in the present embodiment. In addition to this, it is preferable to determine whether or not the duty D is a lower limit (for example, 5%) or more (# 32). The reduction amount B can be subtracted from the target rotational speed VT, and when the duty D is equal to or greater than the lower limit value, the target rotational speed VT is subtracted from the predetermined reduction amount B (# 36). This reduction amount B is, for example, −19 rpm / 5 ms.

  As described above with reference to FIG. 5, the reduction amount B does not have to be a constant value, and may be set in a plurality of stages. For example, as shown in FIG. 16, after the process # 32, it is determined whether or not the current position PP is equal to or less than the decrease amount changing position (# 33). When the current position PP is less than or equal to the decrease amount change position, B1 is set as the decrease amount B (# 34), and when the current position PP exceeds the decrease amount change position, B2 is set as the decrease amount B. It is set (# 35). For example, it is preferable that the reduction amount B1 is −19 rpm / 5 ms and the reduction amount B2 is −25 rpm / 5 ms. The greater the amount of displacement of the driven object, the higher the feeling of deceleration. Note that, as described above, it is obvious that the same processing as in FIG. 16 may be executed even in the case of accelerating in a plurality of stages with the increase amount A3 in addition to the increase amount A2.

  When the target rotational speed VT is set in process # 36, feedback control # 20 is executed. As described above with reference to FIG. 14, a known IP control calculation is executed (# 23), and the motor 30 is driven based on the determined duty D. When the deceleration process is executed, since the transition from the feedforward control to the feedback control has already been completed (since it is often completed), the process # 22 is executed without executing the process # 22. After the determination of 21, the IP control calculation of process # 23 is executed.

  A series of processes of process # 31 to process # 20 including process # 36 for reducing the target rotational speed VT by the reduction amount B is a process executed mainly by the deceleration unit 4. In particular, the process 36 is a representative and central process executed by the deceleration unit 4. The main control unit 1 executes feedback control # 20 in cooperation with the speed reduction unit 4, and drives and controls the motor 30 using a predetermined duty D. When the target rotational speed VT reaches the final steady rotational speed VE, the narrow deceleration phase is completed. Accordingly, the subsequent operation may be considered as a steady operation phase (constant speed phase), but since the feedback control # 20 is continued until the motor 30 stops, it may be considered that the deceleration phase continues in a broad sense. In other words, it may be considered that the deceleration phase of zero reduction is continued. As an example, the target rotational speed VT may be reduced to the displacement completion position EP by a reduction amount of about −2 rpm / 5 ms without being fixed to the final steady rotational speed VE.

  In the above description, the increase amount and the decrease amount in the acceleration phase and the deceleration phase have been described to change stepwise or continuously according to the position, but may change according to time. Further, in the above, the case where the slow start and the slow stop are performed is illustrated, but by setting the initial rotational speed VS to a high value, the motor 30 is driven with the maximum duty from the beginning without performing the slow start. Also good. In addition, the case where the slow stop is performed in order to mitigate the impact at the displacement completion position EP is illustrated, but the slow stop is performed when there is no problem even when the impact occurs or when the impact is not structurally generated. It does not have to be. For example, by setting the upper limit rotational speed VL to a high value, it is possible to substantially prevent the slow stop.

  The motor control device of the present invention can use a vehicle seat device 20 (hereinafter, referred to as “seat 20” as appropriate) as a driving object. A seat 20 illustrated in FIGS. 17 to 19 includes a headrest 21, a seat back 22, and a seat cushion 23. The headrest 21 is a part that can support the head of a passenger to be seated. The seat back 22 is a backrest portion having a support surface 22a that faces the occupant's back and can support the occupant. The seat cushion 23 is a seat that can support an occupant facing the occupant's buttocks. Here, the surface (back surface 22 b) opposite to the support surface of the seat back 22 faces the luggage compartment 9 of the vehicle 100. That is, the seat 20 is the rearmost seat in which the back surface 22b of the seat back 22 forms part of the wall surface of the cargo compartment 9 of the vehicle. The seat 20 corresponds to the second row seat if the vehicle is a two-row seat, and the third row seat if the vehicle is a three-row seat.

  The seat 20 is a seat whose posture can be changed between a seating state in which an occupant can be seated and a storage state in which the passenger can be stored in order to enlarge the cargo compartment 9. Since the rear side of the seat 20 is the luggage compartment 9, the seat 20 is in the retracted state, so that the space of the luggage compartment 9 can be expanded and the loading capacity can be increased. There are various forms of the storage state of the sheet 20. As a general storage state, as shown in FIG. 17, the support surface 22 a of the seat back 22 is folded so as to face the seat cushion 23. Furthermore, it may be comprised so that it may accommodate in the recessed part provided in the floor of the luggage compartment in the state folded in this way. Further, as shown in order in FIGS. 18A to 18D, the seat cushion 23 sinks under the floor 9f of the luggage compartment 9, and the seat back 22 is tilted to the position of the seat cushion 23 in the seated state. It is also possible to adopt a form. Since the seat back 22 stands in the seated state, the seat back 22 is tilted and folded in order to enlarge the luggage compartment 9.

  The seat 20 is an electric seat, and the seat back 22 is driven by a motor in the example shown in FIG. 17, and at least the seat back 22 and the seat cushion 23 are driven by the motor in the example shown in FIG. That is, the seat back 22 and the seat cushion 23 correspond to the driving object of the present invention. For example, the seat back 22 is highly likely to be adjusted to various angles by the occupant, and the position (displacement start position SP) at the time of starting the storage varies. However, it is preferable to have a sense of unity in a series of movements leading to storage, and it is preferable to execute the control as described above. Further, when the seat back 22 is folded, it is sufficient to incline forward to the mechanical end point, but it is preferable that the end point is sufficiently decelerated and stopped without causing an impact. Also in this respect, the control as described above is preferable. The same applies to the seat cushion 23, the headrest 21, and the entire seat 20.

  Moreover, the motor control apparatus of this invention can also make the electric slide door 61 of the vehicle 100 illustrated in FIG. 19, and the electric back door 62 into a drive target object. Moreover, although illustration is abbreviate | omitted, the automatic door of a building can also be made into a drive target object.

  As described above, according to the present invention, a series of operations from the start of operation to the end of operation can be completed in the shortest possible time, and the series of operations can be unified without depending on the operation start position. It is possible to provide a motor control device that has a strong resistance to an operating environment such as aging deterioration, environmental temperature, and power supply voltage fluctuation.

1: Main control unit 2: Acceleration unit 3: Limiting unit 4: Deceleration unit 5: Stop determination unit 20: Seat (vehicle seat)
30: Motor A1, A2: Increase amount B, B1, B2: Decrease amount D: Duty DL: Upper limit duty MV: Initial movement amount PP: Current position VE: Final steady rotation speed VL: Upper limit rotation speed VP: Actual rotation speed, Current rotation speed (rotation speed)
VT: target rotational speed Δd: predetermined amount (increase in duty) α: offset value

Claims (9)

The target rotational speed is set for each predetermined calculation period until the target rotational speed of the motor reaches the upper limit rotational speed set according to the position reached from the reference position of the driven object whose position is displaced by being driven by the motor. An accelerating part to increase,
After the target rotational speed reaches the upper limit rotational speed, a speed reduction unit that decreases the target rotational speed of the motor for each calculation cycle;
A main control unit that drives and controls the motor based on the target rotational speed;
A limiting unit that limits the rotation of the motor according to an allowable output allowed by the motor, and
The upper limit rotational speed is a value that decreases as the amount of displacement from the reference position increases with the final steady rotational speed at which the motor is driven at a constant speed as a minimum value, To reduce the target rotational speed according to
When the output of the motor reaches the allowable output, the limiting unit limits the increase in the target rotational speed by the acceleration unit , and sets the target rotational speed to the current rotational speed of the motor ,
The main control unit controls the motor by pulse width modulation, performs feed-forward control until the driven object is displaced by a predetermined initial moving amount from the start of driving, and sets the initial moving amount. In this feedforward control, when the motor rotation speed is lower than the target rotation speed, the pulse width modulation duty is set to a predetermined amount every calculation cycle. each motor controller Ru increases.   The motor control device according to claim 1, wherein the upper limit rotational speed decreases with a decreasing rate that increases continuously or stepwise as the amount of displacement from the reference position increases. Before SL limiting unit, wherein the duty of the pulse width modulation is determined that the output of the motor reaches the allowable output by equal to or greater than a predetermined upper limit duty ratio and sets the duty of the pulse width modulation to the upper limit duty ratio Item 3. The motor control device according to Item 1 or 2. The main control unit, when the difference between the rotational speed of the said target speed motor is equal to or higher than the predetermined tolerance, according to any one of claims 1 to 3 for increasing the duty ratio of the pulse width modulation Motor control device. A stop determination unit that determines that the motor is in a stopped state based on the rotation speed of the motor,
The predetermined amount by which the duty of the pulse width modulation is increased is determined by the stop determination unit from the time when the main control unit determines that the rotation speed is lower than the target rotation speed by a predetermined value. 5. The motor control device according to claim 1, wherein the motor control device is an increase amount that reaches 100% from a duty at the time of starting the motor. The target rotational speed is set for each predetermined calculation period until the target rotational speed of the motor reaches the upper limit rotational speed set according to the position reached from the reference position of the driven object whose position is displaced by being driven by the motor. An accelerating part to increase,
After the target rotational speed reaches the upper limit rotational speed, a speed reduction unit that decreases the target rotational speed of the motor for each calculation cycle;
A main control unit that drives and controls the motor based on the target rotational speed;
A limiting unit that limits the rotation of the motor according to an allowable output allowed by the motor, and
The upper limit rotational speed is a value that decreases as the amount of displacement from the reference position increases with the final steady rotational speed at which the motor is driven at a constant speed as a minimum value, To reduce the target rotational speed according to
When the output of the motor reaches the allowable output, the limiting unit limits the increase in the target rotational speed by the acceleration unit, and sets the target rotational speed to the current rotational speed of the motor,
The main control unit controls the motor by pulse width modulation, performs feed-forward control until the driven object is displaced by a predetermined initial moving amount from the start of driving, and sets the initial moving amount. After the displacement exceeds, the feedback control is executed. When shifting from the feedforward control to the feedback control, the target rotation is added to a value obtained by adding a predetermined offset value to the rotation speed of the motor at the time of the shift. motor control device to update the number. The acceleration section, wherein in the case the main control unit for executing a feedback control when performing the feedforward control, in any one of claims 1 to 6 for increasing the target rotational speed at different growth rates Motor control device. The motor according to any one of claims 1 to 7 , wherein the acceleration unit increases the target rotational speed with an increasing rate that increases continuously or stepwise as the amount of displacement from the reference position increases. Control device. A motor control device according to any one of claims 1-8, a vehicle seat control apparatus for driving a vehicle seat, as the driven object.

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